I have previously blogged about our adult male Blanding's turtle, Skip, and the problems that Blanding's turtles face here in Massachusetts. I have also blogged about the head-start program for Northern red-bellied turtles. Combining those two themes together, today's blog is about the head-start program for Blanding's turtles.

Head-started Blanding's turtles

Blanding's turtle nests are protected with wire cages at several locations in Massachusetts. When the babies hatch in the fall they are sent to several institutions to be raised through the winter. By the following spring, they are large enough to improve their chance of survival, and are released back to the swamps where they were collected.

It isn't possible to determine the gender of baby turtles from the outside, but medical technology is now allowing us to look inside their bodies to determine whether they have testes or ovaries. These images are from a recent procedure we did to check the gender of ten head-started Blanding's turtles. The turtles will be released in a month or so.

The turtles are put under anesthesia, and a small incision is made in front of the hind leg to allow the scope to be introduced into the body cavity. The gonad is located along the front surface of the kidney.

In this image, the testicle is the light tan, smooth, elongated structure in the center of the image. It is only a few millimeters in size, but the scope magnifies it so that we can see it better.

We found that all of the babies were male! The gender of Blanding's turtles, like many turtle species, is determined by the incubation temperature of the egg. If the eggs in a nest were all at about the same temperature, all of the babies will be the same sex. For Blanding's, cooler temperatures produce males. So it is likely that the babies that we examined came from relatively cool nests. The biologists that study these turtles will be looking into this in more detail this summer. We are planning to check some more babies soon, and we are hoping to find some females.

We thank the many individuals and institutions that are working on this project in addition to the New England Aquarium: Zoo New England, Hyla Ecological, Oxbow Associates, Mass Wildlife, and U.S. Fish and Wildlife.

-Dr. Innis

In addition to our sea turtle work, we also work with a number of conservation programs for native freshwater turtles. This is "Skip," a Blanding's turtle. Blanding's turtles are found in marshy wetlands in the northern United States. Here in New England, Blanding's turtles are very rare. In Massachusetts, they are found at only a few locations, with relatively few turtles at each location. In most areas, Blanding's turtle populations are declining due to habitat destruction, road mortality (females are often hit by cars when looking for nest sites in spring), and illegal collection as pets.

Because of this, Blanding's turtles are protected under Massachusetts law as a threatened species. In 2007, Joe Masi, one of the aquarists here at the Aquarium, found a Blanding's turtle during a field survey of a swamp in southeastern Massachusetts. This location was not previously known to have a population of Blanding's turtles and this initial discovery has led to more intensive surveys of the site. So far no additional specimens have been found.

Skip came to the New England Aquarium recently after he was confiscated by state officials. He was being illegally kept as a pet. Unfortunately, he cannot be released back to the wild because we don't know exactly where he came from and he was exposed to a non-native turtle in captivity. Turtles have genetic adaptations to certain geographic areas, and they have a well developed home range. Thus, releasing a turtle of unknown geographic origin carries the risk of introducing genes that are not adapted to that location. Often turtles that are released outside of their home range keep wandering indefinitely, and never join a population. Also, exposure of native turtles to non-native turtles carries the risk of introducing disease into the native population. All of these factors could be devastating for local species.

So ... Skip will live with us at the Aquarium and serve as an ambassador to educate the public about turtle conservation. Please remember that many of our native turtles are threatened or endangered, and be sure not to take such animals out of the wild.
Thanks!!

-Dr. Innis